diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderModel.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderModel.java
index 2109457bd..bde4efbbe 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderModel.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderModel.java
@@ -123,6 +123,7 @@ public class OrderModel implements IOrderModel {
     private IOrderSequenceDAO orderSequenceDAO;
 
     @Override
+    @Transactional(readOnly = true)
     public List<Label> getLabels() {
         return getLabelsOnConversation().getLabels();
     }
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/labels/AssignedLabelsModel.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/labels/AssignedLabelsModel.java
index 62070d2ed..f44d3049f 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/labels/AssignedLabelsModel.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/labels/AssignedLabelsModel.java
@@ -180,6 +180,7 @@ public abstract class AssignedLabelsModel<T> implements IAssignedLabelsModel<T>
         return false;
     }
 
+    @Transactional(readOnly = true)
     public List<Label> getAllLabels() {
         return getLabelsOnConversation();
     }
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/labels/LabelsOnConversation.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/labels/LabelsOnConversation.java
index e25274944..a2f85eef7 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/labels/LabelsOnConversation.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/labels/LabelsOnConversation.java
@@ -37,28 +37,32 @@ public class LabelsOnConversation {
 
     private final ILabelDAO labelDAO;
 
-    private Set<Label> labels = new HashSet<Label>();
+    private Set<Label> labels = null;
 
     public LabelsOnConversation(ILabelDAO labelDAO) {
         this.labelDAO = labelDAO;
     }
 
     public List<Label> getLabels() {
+        if (labels == null) {
+            initializeLabels();
+        }
         return new ArrayList<Label>(labels);
     }
 
     public void addLabel(Label label) {
+        initializeLabels();
         Validate.notNull(label);
         labels.add(label);
     }
 
     public void initializeLabels() {
-        if (!labels.isEmpty()) {
+        if (this.labels != null) {
             return;
         }
         final List<Label> labels = labelDAO.getAll();
         initializeLabels(labels);
-        labels.addAll(labels);
+        this.labels = new HashSet<Label>(labels);
     }
 
     private void initializeLabels(Collection<Label> labels) {
@@ -73,6 +77,7 @@ public class LabelsOnConversation {
     }
 
     public void reattachLabels() {
+        initializeLabels();
         for (Label each : labels) {
             labelDAO.reattach(each);
         }